Many lactic acid bacteria are detected in vegetable foods such as pickles, kimchi (Korean pickles) bread, sake (Japanese alcohol), miso (bean paste) and soy sauce. Professor Sanae Okada of Tokyo University of Agriculture has termed lactic acid bacteria detected in vegetable foods “vegetable lactic acid bacteria” and suggests distinguishing them from lactic acid bacteria derived from animal foods such as fermented milk and cheese (Japanese Journal of Lactic Acid Bacteria, Vol. 13, No. 1, pp. 23-36 (2002)). This is because vegetable lactic acid bacteria differ from animal lactic acid bacteria in growth environments and are capable of utilizing many more kinds of sugars and adapting themselves to more severe environments in terms of antibacterial substance resistance, enzyme resistance, oxygen resistance, etc.
The present inventors have investigated these vegetable lactic acid bacteria and have already reported that fermented milk prepared using the Lactobacillus plantarum strain ONC141 as a starter has the following capabilities: improving human gastrointestinal microflora (Megumi Kumemura, Masamichi Toba, Yoshiro Sogawa, Seiichi Shimizu, Shinzo Kawaguchi, “Enterobacteriology Magazine” 15, 15, (2001)); increasing defecation frequency in constipated adults (Masamichi Toba, Megumi Kumemura, Satoshi Muneyuki, Yoshiro Sogawa, Hisao Yoshizawa, Yoichi Yajima, Yutaka Matsuda, Hajime Iijima “Enterobacteriology Magazine” 15, 21, (2001)); and increasing a host's resistance to oral infection with the pathogenic salmonella S. typhimurium (IgA production enhancement, gastrointestinal tract mucosal stimulation) (Takeshi Ikenaga, Satoko Yamahira, Hideki Nachi, Masamichi Toba, Hiroshi Okamatsu, “Milk Science”, Vol. 51, No. 1, pp. 27-32 (2002)).
The Lactobacillus plantarum strain ONC141 (fermented milk) has the highest enhancement effects on a host's resistance to salmonella infection among known vegetable and animal lactic acid bacteria and is thus considered to be capable of enhancing mucosal immune functions and highly useful for human host defense.
Lactobacillus ONRIC b0240 (FERM BP-100605) has been re-classified as Lactobacillus pentosus based on a method disclosed in “Francoise Bringel, et al., International Journal of Systematic and Evolutionary Microbiology (2005), 55, 1629-1634” which was published after the present application was filed.